The number 6 has a special significance. It represents the Law and Order and also associated with a Karmic Law of cause and effect. Number 6 is a perfect number, symmetrical in all parts, the number of the Soul.
Plums are ready they are not hard as a rock, soft just a little when pressed. I wouldn't use windfall, they are too ripe. If your making jam, it is best to use some underripe with the ripe ones. Last season I added small diced candied ginger to the plum jam. Really turned out nice.
1 Don't put unripe plums in the refrigerator. 2  They won't be able to continue the ripening process in the cold climate, and you'll end up with chill-damaged plums, which are tasteless and mealy. 3  If you aren't in a hurry for the plums to ripen, you can put them in a bowl on the counter instead of in a paper bag.